The best soil for farming in Dwarf Fortress

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Farming on soil is one of the core activities your dwarves must perform during your adventure in Dwarf Fortress. If you participate in the newcomers’ Tutorial portion of your playthrough, the game will introduce you to farming mechanics in the “Planting” section. This involves taking seeds from your Wagon and sowing them on underground farm plots. Of course, you can also farm on the soil of the overworld, but the primary “dwarven” plants can only grow beneath the earth’s surface. According to Planting’s tutorial description, the subterranean soil beneath the ground offers decent terrain for farming, but it is not “rich soil.”

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If you continue reading the tutorial, the Dwarf Fortress’s farming instructions direct you to “dig deeper to find better soil.” As the tutorial stated earlier, farming can be done on loam, clay, or sand, all of which count as soil. However, if you dig below the first layer under the ground level, all you find are unirrigated floor types that cannot produce crops. The reason is that you have not dug deeper enough to discover the best soil for farming in Dwarf Fortress. 

The answer to “what is the best farming soil” for your dwarven plants in Dwarf Fortress can be found in the Farm Plot’s description for the basic soil of the layer beneath the ground’s surface. If you look next to the “Fertilize every season” checkbox, you will see that the subterranean land you are farming on is “Poor Soil.” However, the phrase beneath this label states, “Cavern Soil is best.” For those unfamiliar, Caverns are massive underground biomes that generate far beneath the earth’s surface where your Wagon spawns.